Carburetor



Aug- 1, 1967 E. M. BIMBERG 3,333,833

CARBURETOR Filed March 29. 1965 IN VEN TOR.

United States Patent O 3,333,833 CARBURETOR Elmer M. Bimberg, Detroit,Mich., assignor to The Bendix Corporation, Detroit, Mich., a Corporationof Dela- Ware Filed Mar. 29, 1965, Ser. No. 443,355 2 Claims. (Cl.261-41) ABSTRACT OF THE DISCLOSURE The presentl inventon relates-generally to carburetors and more particularly to an improved idlesystem for carburetors.

The present inventon is an mprovement over the idle system shown inPatent No. 3,269,712 issued Aug. 30, 1966, for Carburetor, and assignedto the assignee of the present inventon.

In the prior application, the idle air bleed is provided |by drillingone or more holes in the idle fuel tube and exposing the drilled holesto the induction passage. In the operation of the carburetor disclosedin the prior application, a slugging effect has been noted on occasions.The slugging effect manifests itself by irregular operation of theengine at idle and is attributed to solid slugs of fuel being dischargedthrough the idle system.

It is an object of the present inventon to provide in a carburetor animproved idling system wherein the idle air bleed system more completelyatomizes the idle fuel supplied to the engine.

It is a further object of the present inventon to provide a carburetorhaving an improved idle system which is simple in construction andrelatively inexpensive to manufacture.

These and other objects and advantages of the present inventon willbecome readily apparent from the following detailed description taken inconnection with the appended drawings in which the single figure is asectional view of a carburetor embodying the present inventon.

Referring now to the drawings, numeral designatcs a carburetor having a'body 12 and induction passage 14 therethrough containing a choke valve16 and a throttle valve 18 mounted therein on opposite sides of an airnozzle or venturi 20. A fuel 'bowl 22 is secured to body 12 by suitablemeans (not shown) and contains an annular float 24 which controls thelevel of fuel in bowl 22 by regulating suitable Valve means (not shown).A main fuel discharge jet 26 is mounted in a fuel well 28 with its'discharge end 30 disposed to discharge fuel into the throat of the airnozzle or venturi 20. Fuel is supplied to main jet 26 from fuel bowl 22by passages 32 in nut 34, fixed restriction 36, idle tube 38, and port40 in tube 38. Air from induction passage 14 is brought through main jetair bleed passage 42 to passage 44 between the jet 26 and well 28 andthrough perforations 46 to form a fuelair emulsion in main jet 26 priorto discharge from the end 30.

Patented Aug. I, 1967 ICC Idle tube 38 is preferably, but notnecessarily, coaxial with main jet 26 and extends transverse theinduction passa-ge 14 through a bore or passage 47 in the nozzle orventuri 20. One end 49 of idle tube 38 is secured to adjustable nut 48threadedly mounted in body 12. Rotation of the adjustable nut 48 movesidle tube 38 axially in main jet 26 to bring port 40 into vaiiableregistration with a wall 50 formed in main jet 26. The port 40constitutes the main metering restriction, the area of which may beregulated through variable registration with Wall 50.

Idle tube 38 is provided with a plurality of fuel discharge ports 52which communicate with idle passage 54 formed in the side wall of thecarburetor body 12. A plurality of discharge ports 56, 58 and 60 connectidle passage 54 with the induction passage. An adjustable needle valve62 controls the area of -discharge port 60. The bore or passage 47 islarger than the idle fuel tube 38 and the clearance 64 'between thepassage 47 and the tube 38 forms an annular idle air bleed incommunication with the induction passage. Air passing through annularair bleed 64 sweeps all around idle tube 38 and is brought into intimateand turbulent contact with fuel discharged through port means 52.Passage means 54 connects port means 52 and idle air bleed 64 to thedischarge ports 56, 58 and 60 from which the idle fuel is discharged ina highly atomized state.

Although the present inventon has been described with reference to apreferred embodiment, it will be readily apparent to one skilled in theart that various modifications can be made without departing from thespirit of the inventon.

I claim:

1. A carburetor having a fuel 'bowl and induction passage with athrottle therein, a main fuel discharge jet communicating with saidinduction passage at a nozzle portion of restricted cross section, anidle tube transversely mounted in said induction passage, an annularidle air 'bleed surrounding said idle tube and communicating with saidnozzle at substantially the same cross sectional portion of said nozzlewherein said main fuel discharge jet communicates, means connecting saidtube to said fuel bowl, fuel discharge port means in said idle tubeadjacent said idle air bleed, and passage means connecting said portmeans and idle air bleed to the induction passage downstream of saidthrottle.

2. In a carburetor having a fuel bowl and induction passage with an airnozzle of restricted cross section and a throttle therein, a transversepassage formed in said nozzle, conduit means connecting said transversepassage with the induction passage 'downstream of said throttle, an idletube extending across said induction passage into said transversepassage and being radially spaced therefrom, means connecting said idletube to said fuel bowl and port means in said tube adapted to dischargeinto said transverse passage.

References Cited UNITED STATES PATENTS 2,656,l66v 10/1953 Foster 261-412,656,167 `10/ 1953 Phillips 261-41 2,827,272 3/1958 Phillips 26l 413,233,878 2/1966 Phillips 261-41 X HARRY B. THORNTON, Primary Examner.TIM R. MILES, Assistant Examiner.

1. A CARBURETOR HAVING A FUEL BOWL AND INDUCTION PASSAGE WITH A THROTTLETHEREIN, A MAIN FUEL DISCHARGE JET COMMUNICATING WITH SAID INDUCTIONPASSAGE AT A NOZZLE PORTION OF RESTRICTED CROSS SECTION, AN IDLE TUBETRANSVERSELY MOUNTED IN SAID INDUCTION PASSAGE, AN ANNULAR IDLE AIRBLEED SURROUNDING SAID IDLE TUBE AND COMMUNICATING WITH SAID NOZZLE ATSUBSTANTIALLY THE SAME CROSS SECTIONAL PORTION OF SAID NOZZLE WHEREINSAID MAIN FUEL DISCHARGE JET COMMUNICATES, MEANS CONNECTING SAID TUBE TOSAID FUEL BOWL, FUEL DISCHARGE PORT MEANS IN SAID IDLE TUBE ADJACENTSAID IDLE AIR BLEED, AND PASSAGE MEANS CONNECT-